BOSTON The two planes that pierced the North and South towers of the World Trade Center in New York City 11 years ago Tuesday departed from Boston’s Logan International Airport — a fact that heightened scrutiny at Logan, and led to an overhaul of security procedures.

Peter DiDomenica, a state police veteran, was brought in as Logan’s director of security policy after 9/11.

Since then, through his own private company, DiDomenica has trained airport and mass transit security screeners around the world.

Now a member of the Boston University Police Department, DiDomenica joined Morning Edition Tuesday to discuss airport security.